1. Field of the Invention
Exemplary embodiments of the present invention relate to a method for providing an optical lithography without using a conventional mask for manufacturing a thin-film transistor of a display substrate.
2. Description of the Related Art
Typically, a liquid crystal display (LCD) panel may include a display substrate, a substrate oppositely disposed and facing the display substrate, and a liquid crystal layer interposed between the display substrate and the substrate.
The display substrate may include gate and data lines crossing each other, a thin-film transistor (TFT) formed at intersections between the gate lines and the data lines and connected to the gate lines and the data lines, and a pixel electrode connected to the TFT.
A photo mask is used to form patterns on the substrate. For example, the display substrate may be manufactured using a set of photo masks each masks defining a pattern layer, for example, using a four-mask or a five-mask process.
The four-mask process in which patterns of a gate insulating layer, a semiconductor layer, an ohmic contact layer and a source layer are formed using a single mask, may be employed to form the display substrate so as to simplify the manufacturing process. In this case, a slit mask or a halftone mask may be used to form a channel of the TFT. However, the slit mask and the halftone mask are expensive so that the manufacturing cost of the LCD panel may inevitably be increased.
Furthermore, the slit mask providing a maximum resolution with about 3 μm is at odd with a technical challenge in manufacturing a slit pattern to define a uniform channel having such a very small width.